Transparent layered film, process for producing same, and electrode for touch panel
A transparent layered film is produced by forming an anti-water-mark layer on a first side of a transparent resin layer and forming an uneven structure on a surface of the anti-water-mark layer, wherein the anti-water-mark layer comprises a cured product of a curable composition containing a curable resin, a thermoplastic resin, and a metal oxide particle having an average primary particle size of 1 to 100 nm, and the uneven structure has a roughness average Ra of not less than 0.005 and less than 0.03 μm, a mean spacing of profile irregularities Sm of 50 to 300 μm, an average absolute slope Δa of less than 0.1°, and a ten-point average roughness Rz of less than 0.2 μm. Lamination of the film on a glass-containing upper electrode of a touch screen display prevents scattering of glass fragments produced by breakage of the upper electrode, occurrence of water marks, and sparkling on a high-definition display provided with the film.
1. A transparent layered film comprising:
a transparent resin layer and an anti-water-mark layer on a first side of the transparent resin layer, the anti-water-mark layer comprising a cured product of a curable composition containing a curable resin, a thermoplastic resin, and a metal oxide particle having an average primary particle size of 1 to 100 nm,
wherein the anti-water-mark layer has an uneven surface structure having a roughness average Ra of not more than 0.005 and less than 0.03 μm, a mean spacing of profile irregularities Sm of 50 to 300 μm, an average absolute slope Δa of less than 0.1°, and a ten-point average roughness Rz of less than 0.2 μm.
2. The transparent layered film according to claim 1 , wherein the curable resin has three or more polymerizable groups.
3. The transparent layered film according to claim 1 , wherein the curable resin comprises a first curable resin having four or less polymerizable groups and a second curable resin having five or more polymerizable groups.
4. The transparent layered film according to claim 1 , wherein the thermoplastic resin comprises a cellulose derivative, the metal oxide particle comprises at least one particle selected from the group consisting of an antimony-containing tin oxide, an antimony oxide, a tin oxide, and a zinc oxide.
5. The transparent layered film according to claim 1 , wherein a ratio of the metal oxide particle is 0.05 to 2 parts by weight relative to 100 parts by weight of the curable resin.
6. The transparent layered film according to claim 1 , wherein the curable composition further comprises a leveling agent.
7. The transparent layered film according to claim 1 , which has a haze of 0.2 to 1%.
8. The transparent layered film according to claim 1 , which further comprises a low-refraction layer on the anti-water-mark layer.
9. The transparent layered film according to claim 1 , which further comprises an adhesive layer on a second side of the transparent resin layer.
10. The transparent layered film according to claim 1 , which is an anti-shatter film for being disposed inside an upper electrode substrate of a touch screen display to prevent broken pieces of a glass from scattering, wherein the substrate contains the glass.
11. An upper transparent electrode for a touch screen, the upper transparent electrode comprising:
a transparent electrode substrate being a laminate of a transparent conductive layer and a glass substrate and
a transparent layered film recited in claim 9 ,
wherein the transparent layered film and the transparent electrode substrate are laminated with the adhesive layer of the transparent layered film facing the transparent conductive layer of the transparent electrode substrate.
12. The upper transparent electrode for a touch screen according to claim 11 , which is an upper transparent electrode for a capacitive touch screen.